JPH03694B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an azimuth adjustment mechanism, and more particularly to a mechanism used in tape recorders and the like, which enables independent azimuth adjustment in forward and reverse travel.

(Prior Art) FIG. 3 shows an azimuth adjustment mechanism used in a conventional auto-reverse cassette deck and the like.
In the mechanism shown in the figure, a magnetic head 1 is attached to a head support plate 2, and the head support plate 2 is attached to a head mount 3 with two screws. That is, one end of the head support plate 2 is fixed to the head mount via a spacer 4 and a head fixing screw 5, and the other end of the head support plate 2 is fixed to the head frame via a coil spring 7 by an azimuth adjustment screw 6. It is fixed to the pedestal.

In order to perform azimuth adjustment in the mechanism shown in FIG. 3, the azimuth adjustment screw 6 is adjusted while running a standard tape for azimuth adjustment so that the reproduction output is maximized.

However, in auto-reverse cassette decks and the like, the running state of the tape is generally different between forward running and reverse running, so a phenomenon occurs in which the peak point of the playback output deviates between forward running and reverse running, as shown in FIG. In other words, in forward running, the azimuth angle T _F
The reproduction output level is maximum at the point of , while the reproduction output level is maximum at the azimuth angle _TR in reverse driving. For this reason, in the past, adjustments were made to the azimuth angle T _A as a compromise.
In both forward driving and reverse driving, the playback output level was lower than the highest point, resulting in a decrease in high frequency characteristics, a deterioration of the SN ratio, and a deterioration in the workability of azimuth adjustment.

Furthermore, in order to eliminate such inconveniences, a mechanism has been proposed in which azimuth adjustment is performed using independent adjustment screws during forward travel and reverse travel. (Refer to Utility Model Application No. 57-142433). This mechanism has separate azimuth adjustment screws that come into contact with the cylindrical member during forward and reverse travel, making it possible to adjust the azimuth using separate adjustment screws depending on the travel direction. It is becoming.

However, in such a conventional azimuth adjustment mechanism, the tip of the azimuth adjustment screw slides on the cylindrical member when switching the running direction, so the tip of the adjustment screw wears out, and the azimuth adjustment mechanism There was an inconvenience that the durability of the product deteriorated.

(Problems to be Solved by the Invention) In view of the above-mentioned problems with the conventional type, the present invention provides an azimuth adjustment mechanism that allows adjustment to the best azimuth angle for each tape running direction, and improves the durability of the mechanism. The purpose is to improve sexuality.

(Means for Solving the Problems) According to the present invention, in order to solve the above-mentioned problems, a cam member having separate contact portions for forward travel and reverse travel and a switching cam portion; A head support plate having separate adjustment screws that can come into contact with each contact part of the cam member and a driven part that can come into contact with the switching cam part, and a head that is in a fixed relationship with the head support plate. By moving the cam member according to the running direction, it is possible to adjust the azimuth of the head using separate adjustment screws for each running direction, and when the cam member is moved, the cam part and the driven part An azimuth adjustment mechanism is provided, characterized in that the contact portion and the adjustment screw are separated from each other by bringing them into contact with each other.

(Function) According to the present invention, by using the above-mentioned means, different adjusting screws and contact portions come into contact depending on the running direction, so that adjustment can be made to the best azimuth angle for each running direction. becomes possible. Furthermore, when the running direction is switched, the adjustment screw and the contact portion are separated from each other, so that the tip of the adjustment screw and the like are prevented from being worn out, and the durability of the mechanism can be improved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.
FIG. 1a is a front view of an azimuth adjustment mechanism according to an embodiment of the present invention, and FIG. 1b is a partial sectional view of the mechanism shown in FIG. 1a. 2 shows the mechanism shown in FIGS. 1a and 1b from the side. In the mechanism shown in these figures, a magnetic head 11 attached to a head support plate 10 is fixed to a head fixing plate 13 by a head fixing screw 12. The head fixing plate 13 is elastically supported at one end by a head mount 16 by a fixing screw 14 and a head support spring 15. Note that 17 is a spacer fixed to the head frame 16, and the upper limit of the head fixing plate 13 is regulated by the spacer 17 and the fixing screw 14.

The other end of the head fixing plate 13 is provided with two azimuth adjustment screws 18 and 19, which are used depending on the running direction.
A driven portion 20 is formed integrally with 3. Note that 33 and 34 are coil springs that prevent play between the azimuth adjustment screws 18 and 19 and the head fixing plate 13.

On the other hand, a cam member 21 is rotatably attached to the head mount 16 side around a shaft 22, and the cam member 21 is moved by the movement of a direction switching member 23 such as a channel switching lever according to the tape running direction. Rotated. The cam member 21 includes a cam part 24 that can come into contact with the driven part 20, a contact part 25 that can come into contact with the azimuth adjustment screw 19, a contact part 26 that can come into contact with the azimuth adjustment screw 18, and a direction switching member. 23
It has a lever part 27 that engages with the lever part 27. Further, the cam member 21 includes stopper portions 28 and 29.

Further, the head fixing plate 13 is pressed toward the head frame 16 by a spacer 30 fixed to the head frame 16, a fixing screw 31 screwed into the spacer 30, and a spring 32.

In the azimuth adjustment mechanism having the above configuration, azimuth adjustment is performed separately for each running direction by moving the direction switching member 23 in the direction of arrow A or B. Direction switching member 23
In the illustrated state in which the cam member 21 is moved in the direction of arrow A and the stopper portion 28 of the cam member 21 is in contact with the stopper 36 provided on the head frame, the cam member 2
The contact portion 25 of the head 1 is in contact with the tip of the azimuth adjustment screw 19, and therefore, in this state, the azimuth adjustment of the head 11 can be performed using the azimuth adjustment screw 19. At this time, the tip of the azimuth adjustment screw 18 is not in contact with any part of the cam member 21.

When switching from the above-mentioned state, for example, the forward running state, to the reverse running state, the direction switching member 23 is moved in the direction of arrow B. As a result, the cam member 21 is rotated about the shaft 22. At this time, the driven part 20 is lifted upward by the cam part 24, and the azimuth adjustment screws 18 and 19 are moved to the contact part 26 together with the head fixing plate 13.
and spaced upwardly from 25. Then, when the cam member 21 is further rotated and the stopper part 29 comes into contact with the stopper 35 provided on the head frame 16, the tip of the azimuth adjustment screw 18 and the contact part 26 come into contact with each other, and the azimuth adjustment screw Azimuth adjustment is performed by 18. At this time, the tip of the azimuth adjustment screw 19 and the contact portion 25 are separated from each other.

In this way, by moving the direction switching member 23 in the direction of the arrow A or B, the cam member 21
Switching is performed by rotating the tape so that a separate azimuth adjustment screw comes into contact with the contact portion for each running direction, and azimuth adjustment can be performed independently for each tape running direction. In addition, during the switching of the running direction, each azimuth adjustment screw 18, 19 and the contact portions 26, 25 of the cam member 21 are separated from each other, so that wear of the tip of the azimuth adjustment screw and each contact portion is prevented. It can be prevented.

(Effects of the Invention) As described above, according to the present invention, the azimuth adjustment can be performed independently for each traveling direction, making the azimuth adjustment work extremely easy. In addition, it becomes possible to adjust to the best condition for each running direction, and the frequency characteristics can be significantly improved. Furthermore, according to the present invention, since the tip of each adjustment screw does not come into contact with the cam member when switching the running direction,
Adjustment deviations due to wear of various parts will no longer occur, making it possible to significantly improve the durability of the mechanism.

[Brief explanation of the drawing]

Figure 1a is a front view showing an azimuth adjustment mechanism according to an embodiment of the present invention, Figure 1b is a partial sectional view of the azimuth adjustment mechanism in Figure 1, and Figure 2 is Figure 1a.
3 is a front view showing a conventional azimuth adjustment mechanism, and FIG. 4 is a graph showing the characteristics of the azimuth adjustment mechanism shown in FIG. 1: Head, 2: Head support plate, 3: Head mount, 4: Spacer, 5: Head fixing screw, 6: Azimuth adjustment screw, 7: Spring, 10: Head support plate, 11: Head, 12: Head fixing screw ,1
3: Head fixing plate, 14, 31: Fixing screw, 1
5, 32, 33, 34: coil spring, 16: head frame, 17, 30: spacer, 18, 19: azimuth adjustment screw, 20: driven part, 21: cam member, 22: shaft, 23: direction switching member, 24 :Cam part, 25, 26: Contact part, 27: Lever part, 2
8, 29: Stopper part, 35, 36: Stopper part.

Claims (1)

[Claims] 1. A cam member having separate contact portions for forward travel and reverse travel and a switching cam portion, and a separate adjustment screw that can come into contact with each contact portion of the cam member, and the switching cam. A head support plate having a driven part that can come into contact with the head support plate, and a head fixedly connected to the head support plate, and by moving the cam member according to the travel direction, separate adjustments can be made for each travel direction. The azimuth of the head can be adjusted using a screw, and when the cam member is moved, the cam part and the driven part are brought into contact with each other, so that the contact part and the adjustment screw are separated from each other. Azimuth adjustment mechanism.